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31.
Easton R. White Halley E. Froehlich Jessica A. Gephart Richard S. Cottrell Trevor A. Branch Rahul Agrawal Bejarano Julia K. Baum 《Fish and Fisheries》2021,22(1):232-239
The US seafood sector is susceptible to shocks, both because of the seasonal nature of many of its domestic fisheries and its global position as a top importer and exporter of seafood. However, many data sets that could inform science and policy during an emerging event do not exist or are only released months or years later. Here, we synthesize multiple data sources from across the seafood supply chain, including unconventional real‐time data sets, to show the relative initial responses and indicators of recovery during the COVID‐19 pandemic. We synthesized news articles from January to September 2020 that reported effects of COVID‐19 on the US seafood sector, including processor closures, shortened fishing seasons and loss of revenue. Concerning production and distribution, we assessed past and present landings and trade data and found substantial declines in fresh seafood catches (?40%), imports (?37%) and exports (?43%) relative to the previous year, while frozen seafood products were generally less affected. Google search trends and seafood market foot traffic data suggest consumer demand for seafood from restaurants dropped by upwards of 70% during lockdowns, with recovery varying by state. However, these declines were partially offset by an increase (270%) in delivery and takeout service searches. Our synthesis of open‐access data sets and media reports shows widespread, but heterogeneous, ramifications of COVID‐19 across the seafood sector, implying that policymakers should focus support on states and sub‐sectors most affected by the pandemic: fishery‐dependent communities, processors, and fisheries and aquaculture that focus on fresh products. 相似文献
32.
The implications of increasing variability of fish landings 总被引:1,自引:0,他引:1
33.
Phenol in phenol formaldehyde (PF) resin has been partly substituted with lignin extracted from sugarcane bagasse. In order to optimize the lignin-based resin for applications in coating and composite materials, thermal and rheological tests were performed with different wt% of lignin substitution into PF resins. Differential scanning calorimetry scans showed a small exothermic peak and a large endothermic peak, typical of resins. The Tg of the resins was seen between 125 and 150 °C and this transition was clearly evident when the lignin content was increased from 10 to 40 wt%. Increasing the lignin content in the PF resin increases the rate of cure and the heat of reaction. Water absorption tests show that the lignin-PF resin films are effective water-barrier coatings for cardboard substrates. It is speculated that the interaction between the substrate and the lignin-PF resin has resulted in a negative surface charge which would have contributed to the reduction in the contact angle. 相似文献
34.
Halley JW 《Science (New York, N.Y.)》1978,199(4324):6-7
35.
- 1. Mapping of seabed habitats is increasingly being used to identify the distribution and structure of marine ecosystems and as surrogate measures of biodiversity for marine protected area (MPA) planning. In this study, the distribution of seabed habitats to the 3 nmi limit around the Kent Group of islands, south‐eastern Australia were mapped using video ground‐truthed single‐beam acoustics at the mesoscale level (10 m to 1 km) as part of an MPA planning process.
- 2. Six distinct seabed habitat types (continuous reef, patchy reef, sand, hard sand, sparse sponge, and seagrass) were identified based primarily on visual differences in the first and second echo and a further four (low, medium and high profile reef, and sand hills) on variations in seabed profile identified in the echogram. Extensive acoustic and video transects allowed an estimate of the broad‐scale spatial distribution of seabed habitats defined at several hierarchical levels and provided information on the cover of the dominant benthic species or assemblages.
- 3. The island group supports a range of consolidated habitats, including rocky reefs of varying profile dominated by the macroalgae Phyllospora comosa and Ecklonia radiata in depths down to around 45 m, adjacent to deeper sponge‐dominated reefs containing encrusting, erect and branching forms. Unconsolidated habitats occurred broadly through the island group, with the offshore region dominated by hard sand (sand with scallop shells and/or shell grit) and sparse sponge‐habitats (sand interspersed with low cover of sponge‐dominated assemblages). The sheltered coves were dominated by sand and seagrass habitats consisting of beds of the seagrasses Halophila australis, Zostera tasmanica and Posidonia australis, with variations in species composition, patchiness and percentage cover evident within and between coves.
- 4. In February 2004 the Kent Group MPA was announced, covering all waters out to the 3 nmi limit containing two areas defined as a Sanctuary Zone (‘no take’) and a Habitat Protection Zone (‘restricted take’). Overall, seabed habitat mapping generated a capability to define the boundary and size of potential MPA zones within the Kent Group of islands and was an essential component of the planning process to improve the likelihood that the MPA was comprehensive, adequate and representative (CAR).
- 5. The need to define habitats at multiple scales within a hierarchical classification scheme that are meaningful in terms of biodiversity and CAR principles and identifiable using mapping techniques is discussed.